The AOR ARD9900 Digital Voice and Image Interface is a commercial, government, export version of the ARD-9800. Unlike the ARD9800, the ARD9900 features sophisticated voice encryption. This device uses the same audio frequencies (300 - 2500 Hz) as microphone audio. You keep your ability to communicate in conventional analog mode as you can easily shift between digital and analog operation. No rig modifications are required. You simply make connection to your transceiver's mic input and speaker output. [Note: you will have to construct a cable into your radio's mic jack].